1. Field of the Invention
The disclosed concept relates to a switchgear spout that supports current transformers.
2. Background Information
Switchgear devices (e.g., without limitation, electrical switching apparatus, such as circuit switching devices and circuit interrupters such as circuit breakers, contactors, motor starters, motor controllers and other load controllers), are, typically, removably mounted in an electrical enclosure. That is, the switchgear device includes a housing assembly and an electrical switching apparatus. The switchgear device housing assembly defines an enclosure sized to enclose the electrical switching apparatus. Users prefer the switchgear housing assembly enclosure to have a minimal width. Users, however, have a greater tolerance for deeper (front to back) switchgear housing assembly enclosures.
For the sake of an example, hereinafter the switching device is described as a vacuum circuit interrupter assembly, but it is understood the disclosed concept may be utilized with other types of switching devices. A vacuum circuit interrupter assembly is generally “C” shaped. The vertical portion of the vacuum circuit interrupter assembly includes the vacuum circuit interrupter which has a housing enclosing a vacuum chamber with separable contacts therein. The horizontal “legs” of the vacuum circuit interrupter assembly includes conductors having electrical couplings at their distal ends. The electrical couplings, which may be identified as “finger clusters,” have a relatively large cross-sectional area. The electrical couplings are structured to engage a conductive lug, which may be identified as a “stab,” The stab is in electrical communication with either a line conductor or a load conductor.
The electrical switching apparatus further utilizes one or more current transformers to measure the amount of current flowing through the switchgear. Current transformers, generally, are devices that extend about, e.g. encircle, a conductor. That is, a current transformer includes an opening. The current transformers are, typically, disposed adjacent the switching, device. More specifically, the current transformers are typically disposed about a conductor directly coupled to the vacuum circuit interrupter electrical couplings. The current transformers are disposed on a current transformer support surface (hereinafter a “CT support surface”) that extends about a non-conductive body, hereinafter identified as a “spout.” That is, the spout extends through the current transformer opening. The spout has a cross-sectional area sufficient to accommodate the vacuum circuit interrupter electrical couplings which, as noted above, have a relatively large cross-sectional area.
This is a disadvantage, or problem, in that this configuration requires the current transformers to have a greater cross-sectional area than the spout which, in turn, has a greater cross-sectional area than the vacuum circuit interrupter electrical couplings. More specifically, this is a problem because the larger the current transformers, the wider the switchgear housing assembly enclosure is required to be. As noted above, it is desirable to provide a switchgear housing assembly enclosure with a minimal width. Further, it is noted that such spouts are a body that is unitary with the current transformer support surface because there is no need to have a CT support surface that is separable from the spout body.
There is, therefore, a need for a spout assembly having a portion with a reduced cross-sectional area that acts as the CT support surface. In such a configuration, there is a further need for the CT support surface to be separable from the spout body so that current transformers having an opening that is smaller than the spout cross-sectional area may be installed. There is a further need for a spout that may be used with existing vacuum circuit interrupters.